Putting Their Noses to the Test

Several animals and insects are known for their keen sense of smell. Because of their scent perception, many are now being used in special and interesting ways that you may not know about. Dogs, mice, honeybees, and other animals and insects are helping to sniff out cancer, other diseases, and more. Below is a list of these amazing creatures and what they are being used to detect.

Dog: Most of us are aware that dogs have a powerful sense of smell and are relied on by law enforcement for things such as tracking criminals and sniffing out drugs. But, did you know that canines can detect the presence of volatile organic compounds (VOCs) from different types of cancers and other diseases? Scientists have found that dogs’ sense of smell is 10,000 times greater than humans’. While our noses contain about six million olfactory receptors, dogs have as many as 300 million. In addition, the area of the brain that is used to interpret odor is 40 times greater in a dog compared to a human.

Fruit Fly: These insects have highly developed odor receptors. Research shows that cancer odors elicit a response in fruit flies. Like dogs, fruit flies can detect the distinct smell of VOCs from cancer cells, even at low concentrations.

Mouse: Mice have also been used to sniff out illnesses, but in other creatures. For example, these rodents were successfully trained to detect the avian flu in domestic poultry in areas of Asia. Mice are able to smell other pathogens also, and researchers continue to work with them in hopes that these animals can help with quicker response times to potentially deadly virus outbreaks.

Rats: Belgian scientists have tapped into the highly sensitive sense of smell of the giant African pouched rat. The rats have been trained to detect the odor of TNT and other explosives. Their main job has been to sniff out unexploded land mines by scratching and biting at the ground. These rats are led on leashes and can cover 180 square yards in a half hour. In addition, these animals are a good choice for the job because they are cheap to train, small and easy to transport, light enough to keep from tripping the explosive, and have a natural resistance to tropical diseases.

Honeybees: These insects are also being taught to sniff out explosives. Honeybees can detect bomb residue to a part-per-trillion ratio.

Scientists are taking steps to make robots with the sniffing sensitivity as precise as these animals’ but readily admit that the natural scent perception of the animals is above and beyond anything man-made.